Addresses are written for people and read by machines
A surprising share of delivery failures are failures of language.
An address is a piece of natural language pretending to be a coordinate. It carries abbreviations, local knowledge, historical quirks, informal building names and assumptions about what the reader already knows. A human reading it can often work out that the unit number is at the front, that the street has a similarly named twin in the next suburb, or that the block has two entrances and only one of them is used. A sorting system reading it at high speed can do none of that. It matches text to a record, and if the match is ambiguous, something has to guess.
The failure modes follow directly. Duplicated or very similar street names across neighbouring suburbs. Unit and street numbers that can be read in either order. Large sites with many doors but a single registered address. New developments that exist physically well before they exist in any address database. Business premises tucked inside residential buildings. Rear dwellings that share a number with the house in front. In each case nothing is wrong with the parcel and nothing is wrong with the label; the problem is that the description was never precise enough to be read by a machine, and nobody noticed until the moment it mattered.
The practical response, if you are the one sending or receiving, is to write for a reader who has never been to your street and never will be. Put the unit and the street number in the standard order for your country, spell the suburb out rather than abbreviating it, include the postcode, and use the delivery note field for the things a database cannot hold, such as which gate opens, where the entrance actually is, and what the building is called by the people who live in it. It is thoroughly unglamorous, and it prevents more failed deliveries than any tracking feature ever built.